Grinding machine



July 2, 1935. F. J. THELER 2,006,724

GRINDING MACHINE Filed Sept. 25, 1931 4 Sheets-Sheet l f0 15 2? 24 m 2 j? f5 7 Z4 Z9 Z9 35; iii? L l f 12 WHIMIIH I. v NIH 1''.- Z inventor fiPf /fi/or fZ/f/f/P F. J. THELER July 2, 1935.

GRINDING MACHINE Filed Sept. 25, 1931 4 Sheets-Sheet 2.

Cttorne July 2, 1935*. ELER 2,006,724

GRINDING MACHINE Filed Sept. 25, 1931 4 Sheets-Sheet 5 C. z; I a L 10 J0 6 do 6/ 4'7 if Z/ Y 11 lea- 9 Enventor (Ittorneg July 2, 1935.

F. J, THELER 2,006,724

GRINDING MACHINE Filed Sept. 25, 1931 4 Sheets-Sheet 4 Bnnentor fFf f/P/r/r izqff i I BE WW Gnorneg Patented July 2, 1935 GRINDING MACHINE Frederick J. Theler, Cincinnati, Ohio, assignor to Cincinnati Grinders Incorporated, Cincinnati, Ohio, a corporation of 01110 Application September 25, 1931, Serial No. 565,112

22 Claims.

This invention relates to improvements in grinding machines and especially to improvements in a machine for grinding formed work pieces.

An object of the invention is the provision of a machine particularly adapted for rapidly grinding the sides and bottom of the shifter fork groove in transmission gears concentric with the bore thereof.

Another object of the invention is the provision of improved means for positioning the gear groove relative to the grinding Wheel and for effecting the proper rotation of the gear.

A further object of this invention is the provision of a semi-automatic grinding machine in which the work piece is located relative to a supporting spindle and grinding wheel so that a particular portion of the work is opposite to the grinding wheel; the work piece held on the spindle against accidental displacement and subsequently released and automatically ejected or stripped from the supporting spindle.

Other objects and advantages of the present invention should be readily apparent by reference to the accompanying drawings illustrating one embodiment of the invention and described in the following specification and it is to be understood that any modifications may be made in the exact structural details there shown and described within the scope of the appended claims without departing from or exceeding the spirit of the invention.

In the drawings:

Figure 1 is a front elevation of a grinding machine embodying the improvements of this invention.

Figure 2 is a sectional view taken on line 22 of Figure 1.

Figure 3 is a top plan view of the parts within the grinding throat,

Figure 4 is an elevated view of the structure shown in Figure 3.

Figure 5 is a view illustrating certain modifi' cations in positioning, loading and ejecting mechanisms, capable of use in performing the invention.

Figure 6 is a longitudinal sectional view through the friction driving wheel, forming a detail of the invention.

Figure '7 is a top plan view of the machine shown in Figure l and embodying an additional modification.

Figure 8 is a sectional view taken on line 8-8 of Figure 7, showing a number of the parts in elevation.

Figure 9 is a sectional view taken on line 9 -9 of Figure 7 Figure 10 is a sectional "view taken on line Ill-Ii] of Figure 7.

Figure 11 is an'end elevation'of certain parts of the work support as seen from line Ill l*of Figure '7.

Figure 12 is a view of a friction connection be tween certain of the parts and forming a detail of the invention.

Throughout the several views of the drawings similar reference characters are employed note the same or similar parts. 7

A device of this invention may comprise a bed or support In having rising therefrom at one end thereof a pedestal'bearing H rotatably supporting the spindle l2 to which is secured for movement therewith the grinding wheel l3. As shown in Figure 2 the grinding wheel is of a width substantially equal to the desired width of the groove id in the work or gear IS. The bed 10 'is'further provided in its upper surface with ways 16 for a lower slide ll movable relative theretotoward and from the grinding wheel. A second or upper to de-'- slide 18 is superimposed on the slide 1 T and guided by ways formed thereonfor movement relative thereto. This slide it carries a head 19 in which is journaled spindle 29 for the friction drive wheel 2|, which effects rotation of the gear or work I5.

as will later appear.

The gear or work i5 is provided with asplined bore receiving a similarly formed arbor 22 which has at one end a tapered shank 23 received in ta pered bore 24 formed in the spindle or sleeve 25. The sleeve or spindle 25 is provided on its forward end with a flange 26 through which cap screws or the'like 21 extend for securing the same to a driving drum'28. Surrounding-the sleeve or spindle 25 is the bushing 29 and bearing sleeve 29' whereby the spindle unit is mounted for rotation in a j our- 1 nal 30 integral with a bracket 3| carried by I the forward end of the slide l1. The driving drum 23 engages with. the active surface of the friction drive or regulating wheel 2|.

The arbor 22 is held in thespindle 25 by means f of a'draw bolt 32 which extends therethrough and has its head abutting an extension 33 of the spiridie. The gear or work I5 is positioned or locked on the arbor22, against axial displacement. by

means of a latch 34 of a width substantially equal T to the width of the groove l4 into which it enters:

The latch 34 is pivoted at 35 intermediate its ends, and has its lower end bifurcated as at 36 receiving the reduced end 31 of the lever 38. The lever 38 is manually actuated about the pivot 39 which secures it to'bracket 3 I. The latch 34 has extending from it intermediate its end an arm 46, to which one end of a spring 4| is secured. The

V 5 other end of the spring 4| is secured at 42 to the thereof a bracket 43 in which is journaled one end an adjusting screw 44. The screw 44-extends beyond the bracket 43 and carries a pilot or hand wheel. The other threaded end of screw 44 isreceived in a nut 46 s'wiveled in the rear wall of the upper slide IS. A lever 41 issecured to the swiveled nut 46 for actuating same relative to the screw, 44 and advancing and retracting slides H and I8 as will later appear. 7 The friction driving. or regulating wheel 2|. is

of the yielding type whereby the surface .of. the;

wheel will .yieldunder unduep'res'sure between'it and the driving drum 28. This wheel may either be made-ofc the. relatively soft material. such :as rubber, or; asshownin Figure 6, have an unyielding surface but so mounted as to be displaced as respectszthe axis of thedriving spindle; 4 As-shown in Figure. 6, thewheelaconsists of a ring 2 la having. 3m secured inits bore a sleeve 48 in which is formed notches 49 receiving driving pins 60, mounted on springs 5 t. within suitable pockets SZ -formed in. V the spider 53. The.spider;53-in turn is keyed or otherwise. secured to spindle I2 Theoperation of the machineis as follows:

The-lever 41' is actuated to position shown in Figure .1 which retractslthe slides H and 18 to separatethe friction driving.:wheel-2|. from the work driving drum 28and clearthe grindingwheel :.|3 from the groove-|4.- The work locking and re--' leasing, handle 38 is actuated in-a counter-clockwkse direction as'seen in Figure 3 to withdraw the latch.34 .from:the.groove, whereupon the gear or work is mounted on the .arbor 22s and the handle 88 -released to permit; the latch to again enter the groove and: alignv the same with the grinding wheel.

Atlthismime the-lever "is actuated ina' counterclockwise direction toward the front of the machinelwhich effects theshiftingot slide l6 along "the slide toward the work. This movementof theslide." continues until the .frictiondrive'whe el engages the.drivingl drumrfln At this time the playbetween the slidesll and. |8is taken up by the interengagement-of theladjustable stop 54, carried by thearm'fldependingfrom the'slide l8, with the rear-.surfaceof :the lower slide= l1. Continuedmoyementof lever 41,therefor,'effectsthe shifting' ofcxllideslt and-l8 aslajunit relativeto bedwltl to .feedthe work intothe-grinding. wheel and effect 7 a 'stocknrano val :therefrorm: Thetparts: are so arranged that with the' handle in a horizontal position 'as-.compared to thevertical-position; illus-' tratedin Figure 1; the work has been ground-to 65...the desired size whereupon aftera suitable dwell topermit the sparking out of thewheel and work; tharevememovement of the handle retracts the pants-preparatoryto introduction of v a new'unflmshediworkpiecer.

'll'ietfirstr upward amovement of thehandle 41' cal'isesthef-slides 41 and I6. to be retracted as a V unig-sinceany-attempt to move the-slide l8 willcarry withit through thespring 56; secured at iflto thelower slideaand; at 58 tofthe upper slide,-

751thi lower slide llr. movement-oh 'The lever 41 has extending from its inner fac the slides in a rearward direction, or toward the right as seen in Figure 1, continues until the lower slide engages with an adjustable stop 59 extending upwardly from the bed l6 whereupon the lower slide is restrained from further movement 5 permitting the retraction of the friction driving wheel from the drum 28.

The modified structure illustrated in Figure 5 consists of 'a slightly different loading and ejectingmechanism and comprises a bracket 60 in 10 lieu of the bracket 3|, and has at one end a. pair of ears 6| providing a pivotable mounting, such as 62,-.for the arbor 63. The arbor 63 has integral therewith and extending beyond the pivot 62, the handle 64 whereby the said arbor may be oscillated about the pivot. The arbor is pro-. vided with a sleeve 65 loosely journaled thereon and terminating at one end in the drum 66 adapted to be engaged by the regulating or friction driving-wheel 2|. A collar 61 limits the'movement ofthe sleeveon the arbor in one direction. The sleeve 66 has projecting from its one face driving pins 68 adapted to enter bores or holes 59 formed in the face of the work or gear 10 adja-cent thereto. The. gear. 10 has intermediate its ends the groove II to be groundby thegrinding wheel 13; The drum 66 is positioned on the, arbor to. perfectly align the groove with the grinding wheel when the arbor is lowered to its oper-- ative position, which is illustrated in Figure 5. In order to insure the alignment of groove with vthe grinding wheel the bracket 66 carries a 10-.

follows:

After the slides l1 and I8 have-been retracted to their rearmostpositions the arbor (3 throughthe handle 64. oscillated in a counter-clockwise direction thereby carrying the work, from the grinding throat, thereupon thefinished work 'is. removed from the sleeve 65 and an unfinished, workpiece placed thereon. Oscillation of the ar-, bor in a clockwise direction places the workpiece within the grinding throat sothat advancement of slidesl'l and I8 willeffwt the feedingof the work and. grindingwheel aswell as the rotation of the work.

The modification shown in Figures 7 to 13 inclusive illustrates a semi-automatic machine for accomplishing thepurpose of this invention.

As shown in Figure 8 the lever .41 has secured to it a segmental gear 15 meshing with rack teeth fifl'onthe upper adjacent end of the rack bar 8|; This rack bar 8| is provided on its opposite end.

with rack teeth fli meshing with a segmental gear 63 keyed or otherwise secured to a shaft 84 which 601 extends longitudinally of the bed |0al0ng the'rear side thereof. This'shaft 84 operates mechanism 3 for automatically retracting and inserting: the

locating latch as will later appear.

and intermediate its ends a 'pin 85 adapted ,to

operate in an enlarged notch 86 formed in sliding,

arm 81. The notch86 forms a shoulder'88at" the. upper end thereof which co-operates with the pin 85; 1 The sliding arm Misguided in .the brack et 89 extending upwardly from the :lower slides,

|8 and the said arm is provided on the. portion flprojecting belowthe bracket 88 with a ratchet tooth Slice-operating with a shoulder 9| formed on plate 92, keyed or otherwise securedtojtheflli-l cal - shoulder 88.

the lugs 94 and 15 in which is slidably journaled the slide rod 96 having on its forward end the grooved block 8? which receives a roller 83 carried by the free end of an arm 99 which is secured to the forward end of shaft 93 and partake-s of all oscillatory movement of the shaft 93 initiated by the arm 81 through the plate 92 secured to said shaft. The slide rod 96 has secured to it intermediate the lugs 94 and 95 a collar Hit which forms one abutment for a coiled spring iii! surrounding the said slide rod 9t and which spring abuts on its other end with the lug 95.

The end of the slide rod 95 opposite to that to which the block 8! is secured carries an arm It? which is in turn rigidly connected to the corresponding outer end of an ejector rod I83. The ejector rod I83 is journaled in a suitable bore formed through the work supporting bracket 35a which has its axis in substantial vertical alignment with the of the work supporting spindle. The forward end of the ejector rod 33 has secured to its forward end an ejector fork :3, the arms I and I96 of which lie behind the rear face of the workpiece or gear I5 being slightly spaced therefrom during the grinding operation.

The work supporting bracket 3 Ia. has provided on its side face opposite to that on which the lugs 94 and 95 are formed with a bearing lug 101 through which is slidable a rack bar we having the teeth thereof meshing with rack pinion I09 on'the free end of rod or shaft 84. The said pinion IOB partakes of the rotary motion imparted to the shaft 84 through the lever 41 and rack and pinion 8| and 33 for reciprocating the rack bar I68. This bar I98 carries on its free end a cam block I If] having the cam face ill for engagement with the tail I I2 of arm H3 extending from the work locator latch 34a. The cam Hi? oscillates the arm 340. about its pivot against the resistance of a spring II tending at all times to rotate the arm 34a in a counter clockwise direction or into the groove in the workpiece or gear The operation of the parts thus far described in connection with the modification illustrated in Figures 7 to 13 inclusive is as follows:

A workpiece I5 is mounted on spindle 22 and the lever 41 oscillated from the position shown in Figure 8 through substantially 90 in a counter clockwise direction. This movement shifts the rack bar iii to the right as seen in Figure 8 for rotating the shaft 84 clockwise and through the pinions'and gears above described slides the cam rod to the left as seen in Figure for permitting the spring l hi to actuate the latch. 34a. and cause the same to'enter the groove in the gear. Continued movement of the lever 41 operates the parts as above described for effecting the proper rotation of the work, stock removal therefrom and finish thereon; At the conclusion of the grinding operation the lever 41 is returned to position shown in Figure 8. This movement at the beginning thereof withdraws the latch Eda from the groove and eventually picks up the arm 81 through the interengagement of the pin 85 and This axial shifting of the arm 81 rotates the shaft 93 in a clockwise direction and through the arm 92 and block 91 actuates the slide rod 95 to the right as seen in Figure 9, thereby compressing the spring IIII coiled about the rod 96. Near the end of the movement of the lever l"! the arm 8i is disengaged from the plate 92 thereupon the spring WI expands or fires carrying with it slide rod 95, arm I02, ejector shaft H23, and ejector fork I64 thereby forcefully stripping the work from the spindle 22.

After the unfinished workpiece has been mounted on the spindle 22 the lever is again aotuated in a counter clockwise direction for properly locating the work on the spindle through the locator latch Sta and groove in work.

In order that the latch may be the first to come into play for properly locating the work and the first to be disengaged from the work at the conclusion of the grinding operation so as not to interfere with the automatic interjection thereof the following mechanism may be employed. The pinion I69 is keyed on the hub or sleeve I I5 of a member Hi5 which loosely surrounds the shaft or bar 84. A companion member I I! is keyed on the shaft or bar 34 and there is interposed between the members I 68 and I I! a friction driving plate H8 being held under tension by means of a nut H9 on the end of the shaft 84 and clamping the parts between itself and a collar I20 secured to said shaft and lying against the adjacent face of the rack pinion Hi9. Adjustable stop members IZI and I22 are provided for engaging the opposite ends of the rack bar [08 for limiting its movement.

From the foregoing it will be noted that the shaft 84 may be rotated well beyond the amount necessary for disengaging the latch and work or gear groove but that the rack bar I08 will be shifted only the necessary distance whereupon the shaft will rotate idly due to the slippage permitted by the friction l I8. From this it will also be noted that the instant the shaft 84 is reversed the actuation of rack bar I08 will likewise be reversed to the limit of its permissible movement.

What is claimed is:

1. In a grinding machine for grinding formed work pieces comprising a bed, a grinding wheel rota'tably journaled on the bed, a slide on the bed, a work supporting bracket rotatably supporting the work, means for positioning the work on the bracket to align same relative the grinding wheel, a second slide carried by the first slide, a friction driving wheel on the second slide for effecting rotation of the work, and means for actuating the slides independently and as a unit toward and from the grinding wheel.

2. In a grinding machine for grinding formed pieces comprising a bed, a grinding wheel rotatably journaled on the bed, a slide on the bed, a work supporting bracket rotatably supporting the work, means for positioning the work on the bracket to align same relative the grinding wheel, a second slide carried by the first slide, a friction driving wheel on the second slide for effecting rotation of the work, and means for actuating the slides independently and as a unit toward and from the grinding wheel, said means comprising an adjusting screw, a nut carried by one of the slides having an operative engagement with the screw, and a manually actuable lever associated with the nut for actuating same relative to the screw and for effecting a feed between the work and the wheel.

3. In a grinding machine for grinding the shifter fork groove in slidable transmission gears comprising abed agrinding wheel of a width-substantially equal to the width of the.

groove to be ground, a work supporting bracket adjacent the grinding wheel, a spindle journaled in the bracket, the spindle receiving thereon the work or gear to be operated upon and including driving means for'engagement with the gear, means associated with the bracket for aligning the groove in the gear with the grinding'wheel,

logsand means for rotating the spindle and work whilein engagement with the grinding wheel.

14.,In a grinding machine for grinding the shifter fork groove in slidable transmissiongears thecombination of a bed, a grinding wheel of a l5ga width substantially equal to the width of the groove to be ground, a workv supporting bracket adjacent the active face of the grinding wheel,

a spindle rotatably journaled in the branket, the spindle enteringthe bore in the work and hav- "ing complementary driving connections on'the work and spindie, a latch adapted to enter the groove for aligning same with the grinding wheel and for preventing inadvertent disassociation of thework and spindle, means carried by the "bracket for actuating the latch to permit replacement of the work on the spindle and means for rotating the spindle and work.

5. In a grinding machine for grinding the shifter fork groove in slidable transmission gears :theicembination of a bed, a grinding wheel of a width substantially equal to the width of the groove to'beground, a work supporting bracket adjacent the active face of the grinding wheel, a spindle rotatably journaled in the bracket,

-the spindle entering the bore in the work and having complementary driving'connections on the Workand spindle, a latch adapted to enter the "."shifter fork groove in slidable transmission gears a width substantially equal to the width of the groove to be ground, an, opposed friction driving wheel for engagement with the work for-effecting and controlling itsrotation, the grinding wheel and friction driving wheel being spaced from one another to form a work receiving throat therebetween, an arbor inthe throat supporting the work while in simultaneous engagement with the friction driving wheel and grinding wheel,

means adapted to enter the groove at a point spaced from the point'of contact thereof with the grinding wheel for aligning the said groove with the grinding wheel and preventing inadvertent disassociaticn of the work and arbor,

means establishing a driving connection between work and friction,driving'wheel, and means for rendering the aligning means inoperative whereby the work may be changed on the arbor.

'7. In a grinding machine for grinding the the combination of a grinding wheel of a width s'ubstantially'equal to the width of the groove to be ground, a'work supporting bracket adjacent the grinding wheel, an arbor associated with the bracket and supporting. a workpiece'for in slidable transmission gears, the combination of a grinding wheel of' rotation, means carried by the bracket, for, posi tioning the work relative to the-arbor, and align-. ing the groove with the wheel, and means fori rendering the alignment means inoperative whereby the work on the arbor may be removed therefrom.

8.,In fa grinding machine for grinding. the shifter fork groove in transmission gears the.

combination of a-bed, a grinding wheel rotatably supportedby the bed, an. opposed friction drive wheel rotatably supported by the bed, the wheels being spaced from one another to form a grinding throat therebetween, a wo'rksupporting bracket within the grinding throat, a. spindle rotatably journaled'in the bracket, means on. the

spindle forfrictional engagement withithe frietion drive wheel for rotating the work, and means I for ejecting the work from the spindle atythe conclusion of the grinding operation.

9. In a grinding machine forgrindmg the shifter fork groove, in transmission gears the combination of a bed, a grinding wheel rotatably supported by the bed, an opposed friction drive wheel rotatably supported by the bed, thewheels being spaced from one another to form a grinding throat therebetween, the work supporting,

bracket within the grinding throat, a spindle rotatably journaled in the bracket, means. on the spindle for frictional engagement with theIfric- 3 tion drive wheel for rotating the work, means for ejecting the work fromthe spindle atthe. conclusion of the grinding operation, means for locating the work on the spindle for aligning the groove with the grinding Wheel, and means for rendering the locating means inoperative.

10. In a. grinding machine the combination of a bed, a grinding wheel. rotatably journaled thereon, a slide supported by the bed for move-1 ment toward and from the grinding wheel, a

work supporting bracket on the slide, a spindle rotatably journaled on the bracket, means for locating the work on the spindle includingpivotally mounted latch, a lever for actuating the slide toward the grinding wheel to effect relative feed between the spindle and grinding wheel, and means including the lever forrendering the '10- cating latch inoperative and for ejecting the work from the spindle.

11. Ina grinding machine forgrinding the shifter fork groove in slidable transmission gears comprising a bed, a grinding wheel ofa width substantially equalto the width of the groove to be ground, a. spindle having. its axis parallel .with the face of thegrinding wheel and positioned adjacent thereto, the spindle receiving the work to be ground, means for locating the work relative to the spindle for aligning the groove 7 therein with the grinding wheel and comprising a latch adapted to enter the groove at a point diametrically opposed ,to the point of contact with the grinding wheel, an ejector, and means. .for rendering the locator latch inoperative and.

for operating the ejector to strip the workfrom the spindle.

12; In a grinding machine for grinding the shifter fork groove in 'slidable transmission gears comprising a bed, a grinding wheel of a width substantially equal to the width of the groove to be ground, a spindle having its axis parallel with the face of the grinding wheel and posi tioned adjacent thereto, the spindle'receiving the work to be ground, means for locating thefwork relative to the spindle for aligning the groove therein with the grinding wheel and comprlsing a latchadapted to enter the groove at. a 'point'.

diametrically opposed to the point of contact with the grinding wheel, an ejector, means for rendering the locator latch inoperative and for operating the ejector to strip the work from the spindle, said means comprising a lever, and couplings between the lever and ejector and locating latch. V

13. In a device of the class described for grindingthe shifter fork groove in slidable transmission gears the combination of a grinding wheel, a Work supporting bracket adjacent there-. to and including a rotatable spindle, the spindle being adapted to enter the hole in the work or gear, means on the bracket for positioning the gear relative to the spindle and for aligning the groove therein with the grinding wheel comprisg a latch pivotally mounted on the work support, yielding means for actuating the latch about this pivot and inserting same in the groove at a point diametrically opposed to the point of contact with the grinding Wheel, and means for rendering the latch inoperative.

14. In a device of the class described for grinding the shifter fork groove in slidable transmission gears the combination of a grinding wheel, a work supporting bracket adjacent thereto and including a rotatable spindle, the spindle being adapted to enter the hole in the work or gear, means on the bracket for positioning the gear relative to the spindle and for aligning the groove therein with the grinding wheel comprising a latch pivotally mounted on the work support, yielding means for actuating the latch about this pivot and inserting same in the groove at a point diametrically opposed to the point of contact with the grinding wheel, means for rendering the latch inoperative, said means comprising a cam bar, a cam on the bar for engagement with the latch for actuating same about its pivot against the yielding tension of the yielding means, and means for actuating the cam bar.

15. In a device of the class described for grinding the shifter fork groove in slidable transmission gears the combination of a grinding wheel, a work supporting bracket adjacent thereto and including a rotatable spindle, the spindle being adapted to enter the hole in the work or gear, means on the bracket for positioning the gear relative to the spindle and for aligning the groove therein with the grinding wheel comprising a latch piovally mounted on the work support, yielding means for actuating the latch about this pivot and inserting same in the groove at a point diametrically opposed to the point of contact with the grinding wheel, means for rendering the latch inoperative, said means comprising a cam bar, a cam on the bar for engagement with the latch for actuating same about its pivot against the yielding tension of the yielding means, means for actuating the cam bar, and additional means for stripping the work from the spindle when the locating latch is rendered inoperative.

16. In a grinding machine for grinding a selected portion of a work piece concentric with a previously formed portion thereon the combination of a grinding wheel, a spindle adapted to pass through a bore in the work, a bracket adjacent the operative surface of the grinding wheel, means pivotally securing the spindle to the bracket whereby upon oscillation the work is disposed in and out of alignment with the grinding wheel, and means for positioning the work relative to the spindle and grinding wheel.

17. In a grinding machine for grinding a selected portion of a work piece concentric with a previously. formed portion thereon the combination of a'grinding wheel, a spindle adapted to pass through a bore in the work, a bracket adjacent the operative surface of the grinding wheel, means pivotally securing the spindle to the bracket whereby upon oscillation the work is disposed in and out of alignment with the grinding wheel, means for positioning the work relative to the spindleand grinding Wheel, and friction drive: means for effecting rotation of the work relative to the grinding wheel;

18. In a grinding vmachine for grinding a selected portion of a work piece concentric with a previously formed portion thereon the combination of a grinding wheel, a spindle adapted to pass through a bore in the work, a bracket adjacent the operative surface of the grinding I tion drive means for effecting rotation of the work relative to the grinding wheel, said friction drive means comprising a driven member journaled on the spindle, means operatively coupling the member and work for unitary rotation, and a friction drive wheel adapted to be rotated at a relatively slow Work controlling rate of speed and frictionally engaging the member.

19. In a grinding machine of the class described the combination with a bed, of a grinding wheel rotatably mounted thereon, a work rotation and controlling slide carried by the bed for movement toward and from the grinding wheel, a work supporting bracket including a spindle on the slide for rotatably supporting the work, means for locating the work on the spindle to align a selected portion thereof with the grinding wheel, a friction drive member rotatably mounted on the slide for effecting the rotation of the work while it is supported by the spindle in contact with the grinding wheel, and manually actuable means for effecting the movement of the slide to feed the work into the grinding wheel.

20. In a grinding machine of the class described the combination with a bed, of a grinding wheel rotatably mounted thereon, a work rotation and controlling slide carried by the bed for movement toward and from the grinding wheel, a work supporting bracket including a spindle on the slide for rotatably supporting the work, means for locating the work on the spindle to align a selected portion thereof with the grinding wheel, a friction drive member rotatably mounted on the slide for eifecting the rotation of the work while it is supported by the spindle in contact with the grinding wheel, manually actuable means for effecting the movement of the slide to feed the work into the grinding wheel, and means for rendering the locating means inoperative upon retraction of the slide and operable by the manually actuable means.

21. In a grinding machine of the class described the combination with a bed, of a grinding wheel rotatably mounted thereon, a work rotation and controlling slide carried by the bed for movement toward and from the grinding wheel, a work supporting bracket including a spindle on the slide for rotatably supporting the work, means for locating the work on the spindle to align a selected portion thereof with the grinding wheel, a friction drive member rotatably mounted on the slide for effecting :the I rotation. of the work while -:it 'is supported by the spindle 'in contact with the grinding wheel, manually actuable means -for. 'e'fiecting the movement of theslide to feed. tithe work; into the grinding wheel, means for nrendering :the locating means inoperative upon M retraction of the slide and operable by the manually :actuable means, and additional meansfor .;:stripping the work from the spindle when it has ,-:22. In a grinding machine of the class debeen retracted from the grinding wheel.

scribed the combination-with a bed, of a grinding wheel rotatably mounted thereon, a work rotation and'controlling slide carried by the bed for movement toward and from the grinding wheel,

' a work supporting bracket including a spindle on f the slide for rotatably supporting the work, means 'for locating the work on the spindle to align a manually actuable' means, additionar'meansltor selected portion; thereofv'withi the'grindingtiwheel, V a I friction "drive member 'rotatably mounted on the slide for efiecting' the rotation ofthe-v work v while: it isisupported by thespindle in: contact with the grinding wheL'manualIy aetuabl'emeansfor effecting the moiement of-theslide to-feed the work into the grinding wheel, means' ior rendering the locating finope'rative upon retraction of, 'the slide' and operable "byfthe stripping the work fromthe spindle whenfit has been retraetedlirom up:v grinding 'wheelfand -means synchronizing the operation wot'thefllast two mentioned means whereby the work is first m5 released from the spindle and-thenejected there from, I

FREDERICK J .v 

